Chusetts



(No Model-2) G. GR'OMPTON 8v H. WYMAN. LET-OFP MBGHANISM FOR LOOMS.

120.266,351. 2 Patented 001;. 24, 1882.

FEKIp UiviTan STATES PATENT @erica GEORGE OROMPTON AND HORACE WYMAN, OF WORCESTER, MASSA- OHUSETTS, ASSIGNORS TO SAID OROMPTON.

LET-OFF MECHANISIVI FOR LOOIVlS.

SPECIFICATION forming part of Letters Patent No. 266,351, dated October 24, 1882.

Application filed January 23, 188'?.

To all whom it may concern Be it known that we, GEORGE GRoMP'i'oN and HORACE WYMAN, of Worcester, county of Worcester, and State ofMassachusetts, have invented an Improvement in Let-OffMechanisms for Looms, of which the following description, in connection with the accompanying drawings, is a specification.

rlhis invention in looms relates to improvements in the let-olf mechanism, and has t'orits object the production of van organized mechanism whereby the whip-roll, in that class of looms wherein the let'olf is made to depend upon the strain exerted on the warp by the lay as it beats up the lling, is operatively connected with and moves a lever which actuates the pawl and ratchet or equivalent mechanism ofthe let-off, the arms ot' the said lever being made variable automatically through the instrumentality of a pad which is held pressed against the mass of warp on the warp-beam.

By our invention we are enabled to let off the warp uniformly and avoid the greatly-increased strain thereon when the warp-beam is nearly empty, and are enabled to secure greater uniformity in the number of picks to the inch in the fabric being woven.

Figure 1 represents a partial rear side v iew of a snfiicient part of a loom to illustrate one embodiment of our invention; Fig. 2, a right hand end view of Fig. 1, and Fig. 3 a section of Fig. 1 on the dotted line z z.

The loonr-frame'A, ot' any usual or suitable shape, has proper bearin gs for the journals of the warp-beam C, on which is a worm-gear, O2, which is engaged by a worm, C3, on the shaft C", having at its top a hand-wheel, O5. The shaft C, below the hand-wheel, has upon it a ratchet, o, which, to rotate the said shaft and warp-beam intermittingly for the proper distance, is engaged by a pawl, e6, on a pawl-carricr, e5, having its fulcrum on the shaft C4. The

opposite end of the pawl-carrier is connected with the lever p2 by a link, e4. The lever p2 is pivoted upon a bracket, a, attached to the loomframe, and the short arm 3 of the said lever is connected by a rod, p12, with the outer end of a short longitudinally-slotted lever, 1),'looselyl connected at c with the end of a rod, g, and a link,f, having its fnlcrum at 4, the link servwarp by the lay as it beats up` the filling.

(No model.)

ing to support both the rod and the end of the lever b. The other end of the rod g is connected with one end of a lever, h, pivoted at5 `on the loom-flame, and the opposite end of the said lever lt is connected by link t' with the pad k, the shank k2 of which is extended through guides 6 in a plate secured to the loom-frame. The pad lc in practice will rest directly against the mass of yarn or warp o n the warp-beam G, and will be kept pressed against the warp by thevspring m, one end of which isjoined with the lever h and its other with a suitable fixed stud or eye, m2. We have not herein shown the warp-beam as having warp upon it.

rlhe whip-roll G, of usual construction, is carried by a shaft having its ends journaled in suitable bearings of the loom-frame, and the said shaft has projecting backwardly from it an arm, d, upon which is bling the rod a of the mechanism to be described, which keeps the whip-roll pressed upward in a yielding manner in opposition to the stiain exerted on the 1n this our invention the amount ofI warp let oft' depends upon the diameter of the filling, as fully described'in United States Patent No. 192,514, to which reference may be had. The take-np, to co-operate Iwith this let-off, will in practice be substantially as in the said patent. At the lower end ot' the rod n are weights a2, more or less heavy, according to the class of fabric being woven. The descent of the arm d, and the rise of the whip roll to adapt it to the warp being employed, is adjusted by the stop 12 in the. lug 13, as described and claimed in our application tiled January 26, 1882. The lowermost piece of the weight n2, it being fixed to the rod u, has at its rear side a pimp, (see Fig. 3, and dotted lines Fig. 1,) which enters the slot in the lever b. The pad k rises under the action of the spring m as the warp is unwound from the warpwbeam, the diameter of the beam and its mass of yarn then decreasing, and as the pad risesl it moves rod g in the direction of the arrow 10 and shifts the lever b over the pin p carried by the xed part of the Weight a2, so that the weight raised as the whip-roll is depressed by the strain o t' theyarn upon it (the lay then beating in the illing) will raise the outer end of lever b for a greater or less distance, and by the rod p and lever p2 link e4 and pawl-carrier e5 will cause the pawl e", in engagement with the ratchet c, to turn the shat't C4 and warp-beam for a greater or less distance, the distance increasing as the yarn is unwound. Then the pawl-carrier e5, having the pawl c@ for moving theratchet c on the shat't C which, by its worm G3 actuates the let-ofi", is moved directly from an arm fixed to the shaft of the whip-roll G, as in our application filed January 26, i882, the whiproll, when the warp-beam is nearly empty, is obliged to descend so low to insure the delivery ot' a proper amount ot' warp that the strain on the warp is made much greaterin proportion than when the warp-beam is nearly t'ull and the whip-roll does not descend so low. rlhc taking up ot' the cloth also depending, as stated, upon the pressure ot' the lay orits reed against the tillingl at the iell, any increased strain up on the warp hy reason oi" the whip-roll occitpying a lower position will, it is obvious, att'ect the number ot' picks to the inch, other things being equal, but to obviate this` dilliculty and insure greater uniformity in the fabric as to the number of picks to the inch we have devised mechanism whereby the pawl derives its movement from a lever which is variable as to itsthrow, according to variations in the quantity ot' warp on the warpbeam.

The power to lit't the lever band aetuate the pawl c more or less is applied to the lever by the pinp as it is raised and lowered by the rod a and whip-roll, and the lever is gradually moved longitudinally with relation to the pin j) as the yarn is unwound. rlhe whip-roll is herein shown as the source of motion for the lever b to actnate the pawl tf; but by the 1ntervention ofthe lever I), as described, and slidingit on the pin j), the point to which the whip-roll has to descend when the warp-beam is nearly empty to thus secure the delivery of the proper amount ot' warp need not be so low asin the patent and application referred to, and consequently the strain on the warp will be more nnit'orni and the number of picks to the inch be n'iaintained substantially the same, notwithstanding variation in the amount ot warp on the warp-beam.

Instead of the toothed pawl and ratchet c c, we might use a friction-pawl and ratchet ot' any usual construction as equivalents. Instead ot' the slotted lever b and pin p as a coilnection between the rod a and the lever b, it is obvious that the lever might be a round rod and enter or slide through a' hole in the pin p.

XVe claim- 1. The whip-roll, means to keep it pressed up in a yielding' manner against the strain ot the warp on the whip-roll, and a lever the fulcrum ot' which is changeable in its position, and connecting means between the said whiproll and lever, combined with a pad adapted to bear against the warp on the warp-beam, and suitable connecting devices between the said lever and pad, wherebydecreasein the amount of warp on the warp-beam enables the outer end ot' the said lever to be raised a greater distance, substantially as described.

2. The whip-roll, means to keep it pressed up in a yielding manner against the strain ot' the warp on the whipAroll, and a lever the tuicrum ol" which is changeable in its position, and connecting means between the said whiproll and lever, a pad adapted to bear against the warp on the warpheain, suitable connccting devices between the said lever and pad, the warp-beam, the shat't U4, and gearing between it and the warp-beam, combined with a pawl and ratchet and means between the said lever and pawl to actuate said pawl, substantially as described, whereby decrease in the amount ot' warp on the warp-beam enables the outer end ot' the said lever to be raised a greater distance and makes the said pawl and ratchet turn the shaft U* and warpbeam a greater distance by the automatic change of position of the l'ulcruin ot the said lever, as set forth.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

GEO. C KOMPTON. HORACE \VYMAN.

Witnesses:

J. B. SYME, J. A. WARE. 

